The present invention relates to a clamping device for crochet needles (hereafter called "needles"). Such clamping devices are used in galloon crochet machines (also called crochet galloon machines) of the type described, for example, in European patent publication No. 110 271. The clamping device can also be used in Raschel looms. It is always attached to the needle bar in these machines.
There is a need to produce bands with 10 or more threads per centimeter width on a galloon crochet machine or Raschel loom. This is particularly important in the case of elastic bands, such as those used in underwear and sportswear.
It is known from U.S. Pat. No. 4,137,730 that a group of crochet needles may be set into a clamping device, wherein spacers ensure the distance between needles. This allows the needles to be clamped close together, however, if it should be necessary at a later stage to replace a broken needle, the entire group of needles must be released and carefully restored once the needle has been replaced. This represents a considerable waste of time.
On the other hand, it is known from U.S. Pat. No. 3,823,581 that grooves may be milled close together into one of the body pieces of the clamping device, each of which acts as a receptacle for the shaft of a needle.
A similar arrangement is known from the above-mentioned European patent publication No. 110 271, FIGS. 8 and 9. The grooves are at least almost as deep as the height of the shafts. There are limits to the number of grooves which can be milled into a centimeter width of one of the body pieces of the clamping device. If the number of grooves is increased to over ten per centimeter width, ridges of 0.2 mm thickness and less are resulting between the grooves. This cannot be avoided by the use of thinner needles, since the needles must have a certain strength, and the use of needles thinner than 0.4 mm is impractical.
If a gang cutter is used to mill the grooves, it is possible to mill a group of adjacent grooves in one operation, however even then it is technically impossible to mill grooves with intermittent ridges of 0.2 mm or less without this resulting in a relatively high level of wastage caused by broken ridges.
The present invention solves the problem of clamping more than 10 needles per centimeter width in two different ways.